There are countless surgical instruments that are currently used by medical professionals, such as surgeons, dentists, etc. for use in medical procedures, such as, for example, bone fixations and the like. These surgical instruments include, amongst others, saws, drills, screwdrivers and other tools (collectively referred to as "tools"). In many instance, these surgical instruments include battery powered drive mechanisms, or other powered drive mechanisms, in order to drive (e.g., rotate, oscillate, etc.) the surgical tool.
It is well known in the art that these surgical instruments are very complex, yet delicate, instruments which must be used with the utmost care during a surgical procedure. For example, many of these instruments have complex mechanical systems in order to retain the tool within a collet of the surgical instrument such that the tool is firmly retained therein during the surgical procedure. These same tools may also include a mounting and/or locking mechanism in order to hold a battery to the instrument, itself. These locking mechanisms can range from simple clamps to more complex key and lock mounts. It is further realized that many of these surgical instruments, especially drills, screwdrivers and the like have adjustable speed controls in order to allow the surgeon or other medical worker to finely adjust the rotational or oscillating speed of the surgical instrument during the surgical procedure.
In accordance with the many procedures that need to be followed during a surgical procedure, it is necessary for the surgeon or other medical personnel to first prepare the surgical instrument prior to the actual surgical event. This initial procedure includes placing a specific required tool into a collet or chuck (collectively referred to as a "collet") of the surgical instrument, as well as ensuring that the battery is fully charged and properly mounted thereon. Thereafter, the surgeon tests the surgical instrument prior to using the same. This latter step includes testing the speed adjustments on the surgical instrument.
It is well known, however, that many of these procedures may be complicated and time consuming. For example, many of the collets currently used include a key and lock mechanism which is both cumbersome to use and time consuming to adjust. Other collet systems are also known, but have other drawbacks associated therewith. For instance, some collet systems are simply threaded collets mechanisms that apply a certain pressure to the tool in order to retain the tool within the surgical instrument. However, these collet systems tend to allow the tool to slip during use thereof, posing a serious danger to both the patient and the surgeon (or other medical worker).
Once the tool is secured within the collet, the powered drive mechanism of the surgical instrument is then activated in order to power the surgical instrument, itself (e.g, drive the tool). It has been found that the use of a powered drive mechanism in surgical instruments during surgery reduces surgeon fatigue and minimizes the amount of time required to perform a particular surgery. However, even though a drive mechanism may assist the surgeon during surgery, there are times during specific surgical procedures that may require the need for a manual surgical instrument. For example, a surgeon may need to apply a large torque to properly place a screw in a bone during a bone fixation procedure, which cannot be performed with a powered tool because the powered surgical instrument is not designed for that particular torque. In this case, it is necessary for the surgeon to change surgical instruments midway through a surgical procedure in order to manually perform the remaining portion of the surgical procedure. This may pose a danger to the patient.
It is further noted that many powered surgical instruments further succumb to other shortcomings, such as failure of the motor shaft. This occurs when the motor shaft is subjected to exceptionally high torque conditions, which is not uncommon during a surgical procedure. Needless to say, the failure of the motor shaft during a surgical procedure is quite dangerous and also renders the surgical instrument useless for future surgical procedures.
Lastly, the surgeon or other medical personnel must also ensure that the power supply (e.g., battery) is properly mounted on the surgical instrument prior to and during use of the surgical instrument. However, with complex mounting systems, such as, key and lock systems, it may be difficult for the surgeon to properly mount the battery onto the housing. This is especially important in the case of battery failure during a surgical procedure such that the surgeon cannot readily and easily remove the failed battery and replace it with a new battery. Also, it is important to ensure that the battery is properly mounted because it has been found that less complicated battery mounting systems do not adequately retain the battery on the housing of the surgical instrument during a surgical procedure. This, of course, poses the problem of a surgical instrument power failure during a surgical procedure which may pose countless dangers to the patient.
Notwithstanding the above discussion, what is needed is a locking system for both the drive mechanism and battery, as well as a clutch mechanism for the drive mechanism. Such a locking system for the battery would be a keyless system and would be easily allow the battery to be mounted and removed from the housing of the surgical instrument. The locking mechanism for the drive mechanism would preferably allow the surgical tool to be used both as a powered and manual tool, whereby in the manual mode the drive mechanism would be prevented from rotating with respect to the motor of the surgical instrument. Moreover, the clutch mechanism would preferably allow a torque of the driving mechanism to be limited such as to prevent failure of a drive shaft of the drive mechanism. These locking and clutch mechanisms would be easy to manufacture and would be robust.